<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>堆块照监控内存</title>
</head>
<body>
    <button id="btn">
        Add
    </button>
    <script>
        let tempEle

        function fn(params) {
            let ul = document.createElement('ul')
            for(let i = 0; i < 10; i++) {
                let li = document.createElement('li')
                ul.appendChild(li)
            }
            tempEle = ul
            tempEle = null  // 不用了直接 重置为null 分离dom 存在内存泄漏的现象
        }
        document.getElementById('btn').addEventListener('click', fn)
    </script>
</body>
</html>